/Engine/Source/Runtime/Engine/Public/LightMap.h
Incident lighting for a single sample, as produced by a lighting build. FGatheredLightSample is used for gathering lighting instead of this format asFLightSampleis not additive.
struct FLightSample
bool
bIsMapped
True if this sample maps to a valid point on a triangle.
float[NUM_STORE...
Coefficients
Coefficients[0] stores the normalized average color, Coefficients[1] stores the maximum color component in each lightmap basis direction, and Coefficients[2] stores the simple lightmap which is colored incident lighting along the vertex normal.